This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a pilot study that involves the determination of disease specific serum peptide, protein markers in patients with colorectal cancer, pancreatic cancer using isotope dilution tandem mass spectrometry. There are many markers for cancer but their sensitivity ranges between 50% and 90%. Preliminary studies have shown that this tandem mass spectrometer system is highly sensitive which will allow a wider selection of peptides and less variation since it does not depend on an ELISA assay. This study is the first step and will develop a peptide library of potential markers in these patient groups. Response data is not being looked at in this pilot study. The PIs will identify patients with advanced or metastatic disease and normal controls. Initially they will look at the preparation of the blood to determine whether plasma or sera and the temperature of collection would be best. There are a set of 30 peptides which will be used initially but they will look at the top 20 peaks and also see if there are new peptides which are different between normal and the patients. Further evaluation with additional patients will be obtained. This is an early study which seems like it has great potential and exciting possibilities.